Electronic registers and meters taking advantage of the expanded data processing capabilities inherent in such devices have been provided with built in test capabilities, and may include a "test mode" in which various functions and operation of the equipment may be displayed and tested. However, the test mode is not the normal mode of operation and may be actuated and utilized only at those relatively infrequent times when a serviceman is checking or repairing the electronic energy meter. As a result, the switch provided to transfer operation of the test mode has been of the momentary contact type, that is the test mode is actuated and maintained only as long as pressure is maintained to actuate the switch. However, during testing or repair it may become necessary to actuate the test mode for more than a brief period of time. Accordingly, it has become desirable to provide a test mode switch which is not of the momentary contact type. Also, it is desirable to provide a flag or indication that the energy meter has been switched to the test mode to remind the serviceman to turn off the test mode actuator switch when the testing is completed.
In addition, it is desirable in a energy meter that test functions, actuators, and indicators be unobtrusive and not clutter the meter face during the normal periods when meter reading is accomplished by non-service personnel, in order to avoid confusion in meter reading, and also to minimize unintended operation of test functions. Further, the actuator for the test function should be readily accessible yet not obvious to one not aware of its presence.
Notwithstanding that servicemen or technicians normally utilize the test function, it is desirable that actuation of the test function be accomplished without special tools or even a screwdriver.